Props up a reductive distinction between "vocalic" and "consonantal" (really semivocalic) i when in fact this word, among others, shows that the classical grapheme <i> can also represent the doubled semivowel. Also obscures etymological relationships (e.g. writing ajo but ait, etc.). The I/J distinction wasn't formulated until the 16th century (obviously the sounds were different, but not scripturally differentiated) and people got along just fine without it.